This invention relates to absorbent tampons, applicators for use with such tampons, and methods for making such tampons. More particularly, the invention relates to a tampon having improved leakage protection through improved expansion characteristics and the use of independent protection mechanisms.
A wide variety of absorbent catamenial tampons have long been known in the art. Most currently commercially available tampons are made from a tampon pledget which has been compressed into a substantially cylindrical form. Tampon pledgets of a variety of types and constructions have been described in the art. Prior to compression, the pledget may be rolled, spirally wound, folded, or assembled as a rectangular pad of absorbent material. Tampons made from a generally rectangular pledget of absorbent material have been popular and successful in the market.
The absorbent catamenial tampons now in use typically comprise absorbent members which are compressed to a generally cylindrical form about three-eighths to one-half inch (about 1.0 cm to 1.3 cm) in diameter and from about 2 cm to 7 cm in length. In order to provide the desired total absorbency, these absorbent members are usually formed from batts larger in size than the vaginal orifice, which are then compressed to the size (with a corresponding increase in rigidity) indicated above in order to facilitate insertion. As fluid is absorbed, these compressed tampons are expected to re-expand toward their original pre-compressed size, and to eventually become large enough to effectively cover the vaginal cavity against fluid leakage or bypass. While it has been found that these compressed tampons perform their intended function tolerably well, even the best of them do not always re-expand sufficiently, or fast enough, to provide good coverage against leakage.
It has been long recognized that the internal vaginal cavity in its normal collapsed state is of much wider dimension in its transverse plane than in its vertical plane. It is equally well known that the minimum dimension of the vagina is near the introitus while the maximum dimension is near the cervix. It is desirable, therefore, when considering a tampon for catamenial use, to provide a structure which is in its initial state is of a size and/or shape to pass through the vaginal orifice without discomfort, and when once inside the vaginal cavity and beyond the restrictions of the orifice may be expanded, particularly in the lateral direction, to contact substantially all of surface of the vaginal walls from one side to the other in the vaginal cavity to prevent early bypass of the menstrual discharges from the cervix.
The prior art has long recognized various mechanisms by which tampons might fail to deliver superior performance. One such mechanism is often referred to in the art as xe2x80x9cbypassxe2x80x9d failure. Bypass failure occurs when the menses travels along the length of the vagina without contacting the tampon, i.e. the tampon fails to intercept the flowing menses.
A compressed tampon, to perform well, should re-expand as quickly and fully as possible and should be in a form to provide the best possible anatomical fit. Nevertheless, these needs are not always consistent with the desire to provide a tampon which is sufficiently small and rigid enough to facilitate an easy insertion. Additionally, even after use, the tampon should be as comfortable as possible to remove from the vaginal cavity. Prior art tampons, therefore, attempted to balance these design objectives as best as possible, often having to trade some performance with respect to one objective for improved performance with respect to another.
Typical currently marketed tampons will usually expand in use to a width dimension in a range from about 15 mm to about 26 mm. This may be smaller than the width of the vaginal cavity in its collapsed state. In particular, because the maximum width dimension of the vagina is near the cervix, tampons which are placed within the upper third section of the vaginal canal (which is where tampons are often placed) may not always expand sufficiently, particularly in the width direction, to provide superior coverage. Additionally, typical currently marketed tampons may not even be able to achieve the width dimensions given above when under pressure (such as by the pressure of the vagina during use). Another consideration is the rate and nature of tampon re-expansion which may not always be optimal in currently available tampons.
It is, therefore, desirable to provide a tampon with improved expansion characteristics, particularly in the width dimension. Such a tampon should not introduce new drawbacks, such as a decreased ability to comfortably remove the tampon. Ideally, such a tampon should be able to be manufactured out of materials similar to those currently used for tampons. These materials have the advantages of a proven record of suitability for human use, acceptable cost, and the ability to be manufactured into tampons without undue modifications to current commercially available manufacturing equipment.
It has been found that even the best-designed currently available tampons do not always re-expand as designed in a manner to completely eliminate leakage. Therefore, it is desirable to provide a tampon, which in addition to improved expansion characteristics, is provided with an improved leakage protection mechanism which is independent of tampon re-expansion. Ideally, such tampons would also be provided with an improved applicator to enhance to likelihood that the benefits of the tampon will be achieved by a majority of users.
This invention relates to catamenial tampons, and more particularly, to tampons having particularly desired expansion characteristics.
A tampon of the present invention which may be sold as a xe2x80x9cRegularxe2x80x9d absorbent tampon may comprise a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. Subsequent to this compression, the absorbent material preferably has a diameter of less that about 15 mm. The resulting tampon has an absorbent capacity as measured by the standard syngyna test of between about 6 to about 9 grams. The tampon is fluid expanding and preferably has an expanded width upon fluid absorption of at least about 20 mm.
In preferred embodiments the difference between the absorbent material diameter and the tampon expanded width is at least about 6 mm. The difference between the absorbent material diameter and the tampon expanded width may also be at least about 10 mm. Preferably, the mass of absorbent material is subjected to microwave radiation during formation of the tampon.
Another embodiment is a tampon of the present invention which may be sold as a xe2x80x9cSuperxe2x80x9d absorbency tampon. Such a tampon may comprise a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. Subsequent to this compression, the absorbent material preferably has a diameter of less that about 19 mm. The resulting tampon has an absorbent capacity as measured by the standard syngyna test of between about 9 to about 12 grams. The tampon is fluid expanding and preferably has an expanded width upon fluid absorption of at least about 24 mm.
In preferred embodiments the difference between the absorbent material diameter and the tampon expanded width is at least about 8 mm. The difference between the absorbent material diameter and the tampon expanded width may also be at least about 12 mm. Preferably, the mass of absorbent material is subjected to microwave radiation during formation of the finished tampon.
Another embodiment is a tampon of the present invention which may be sold as a xe2x80x9cSuper Plusxe2x80x9d absorbency tampon. Such a tampon may comprise a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. Subsequent to this compression, the absorbent material preferably has a diameter of less that about 22 mm. The resulting tampon has an absorbent capacity as measured by the standard syngyna test of between about 12 to about 15 grams. The tampon is fluid expanding and preferably has an expanded width upon fluid absorption of at least about 27 mm.
In preferred embodiments the difference between the absorbent material diameter and the tampon expanded width is at least about 10 mm. The difference between the absorbent material diameter and the tampon expanded width may also be at least about 15 mm. Preferably, the mass of absorbent material is subjected to microwave radiation during formation of the finished tampon.
Another embodiment is a tampon of the present invention which may be sold as a xe2x80x9cJuniorxe2x80x9d absorbency tampon. Such a tampon may comprise a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. Subsequent to this compression, the absorbent material preferably has a diameter of less that about 15 mm. The resulting tampon has an absorbent capacity as measured by the standard syngyna test of less than about 6 grams. The tampon is fluid expanding and preferably has an expanded width upon fluid absorption of at least about 20 mm. Preferably, the mass of absorbent material is subjected to microwave radiation during formation of the finished tampon.
In an additional embodiment of a tampon of the present invention which may be sold as a xe2x80x9cRegularxe2x80x9d absorbency tampon, the tampon comprises a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. The resulting tampon has an absorbent capacity as measured by the syngyna test of between about 6 grams and about 9 grams. The tampon demonstrates a rate of expansion as measured by the expansion under pressure test from time zero until two minutes of at least about 1.25 mm/min. In another embodiment the tampon may demonstrate a rate of expansion as measured by the expansion under pressure test from time zero until seven minutes of at least about 0.58 mm/min.
In an additional embodiment of a tampon of the present invention which may be sold as a xe2x80x9cSuperxe2x80x9d absorbency tampon, the tampon comprises a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. The resulting tampon has an absorbent capacity as measured by the syngyna test of between about 9 grams and about 12 grams. The tampon demonstrates a rate of expansion as measured by the expansion under pressure test from time zero until two minutes of at least about 1.6 mm/min. In another embodiment the tampon may demonstrate a rate of expansion as measured by the expansion under pressure test from time zero until seven minutes of at least about 0.82 mm/min.
In an additional embodiment of a tampon of the present invention which may be sold as a xe2x80x9cSuper Plusxe2x80x9d absorbency tampon, the tampon comprises a mass of absorbent material which has been compressed into a generally cylindrical, self-sustaining form. The resulting tampon has an absorbent capacity as measured by the syngyna test of between about 12 grams and about 15 grams. The tampon demonstrates a rate of expansion as measured by the expansion under pressure test from time zero until two minutes of at least about 1.39 mm/min. In another embodiment the tampon may demonstrate a rate of expansion as measured by the expansion under pressure test from time zero until seven minutes of at least about 0.87 mm/min.
An additional embodiment of a tampon of the present invention may comprise a chevron shaped laminar pad. The pad has a width and a length wherein the width is greater than the length. The pad may comprise at least three layers of absorbent material, including an uppermost layer, a lowermost layer, and at least one intermediate layer positioned between said uppermost layer and said lowermost layer. Each of the uppermost layer and the lowermost layer is comprised primarily of rayon, and the at least one intermediate layer is comprised primarily of cotton. The tampon also comprises a withdrawal cord attached to the laminar pad. The withdrawal cord comprises secondary absorbent member joined to the withdrawal cord along at least a portion of its extent. Preferably, the secondary absorbent member may be an integral part of at least a portion of the withdrawal cord.